<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <div id="app">    </div>
    <template id="my-app">
        <button @click="change">修改firstName</button>

        <h2>computed属性：{{fullName}}</h2>
        <h2>computed属性：{{fullName}}</h2>
        <h2>computed属性：{{fullName}}</h2>
        <h2>computed属性：{{fullName}}</h2>

        <hr>

        <h2>methods属性：{{getFullName()}}</h2>
        <h2>methods属性：{{getFullName()}}</h2>
        <h2>methods属性：{{getFullName()}}</h2>
        <h2>methods属性：{{getFullName()}}</h2>
    </template>

    <script src="https://unpkg.com/vue@3/dist/vue.global.js"></script>
    <script>
        const App = {
            template:'#my-app',
            data() {
                return {
                    firstName:'三',
                    lastName:'张'
                }
            },
            computed: {
                fullName() {
                    //计算属性是有缓存的，当我们多次使用计算属性时，计算属性中的逻辑只会执行一次，当调用值发生变化时，才会重新执行
                    console.log('computed中的fullName执行了')
                    return this.lastName + this.firstName
                }
            },
            methods: {
                getFullName() {
                    console.log('methods中的getFullName执行了')
                    return this.lastName + this.firstName
                },
                change() {
                    this.firstName = '三三'
                }
            }
        }

        Vue.createApp(App).mount('#app')
    </script>
</body>
</html>